Error allocating memory.

I'm developing a custom QQuickItem control to plot data in a graphic which can be scrolled show all values. I've detected that to store the data, if I use a dynamic container (like a QVector) then application receives a SIGV and the memory could not be allocated, however If the memory is allocated statically in the control (using a C array) then no signal is received and the application works fine.

I'm developing a technical application which I need to plot 4 signals. To plot these signals of data, I'm developing a custom PlotControl, inherited from qquickitem. One of the requirements of the PlotControl is that the user should be able to flick the plot, with a gesture, to display previous data.